round, black object.

"There's Sam!" shouted Grant.

Sure enough. Sam was still alive and without wasting a moment he struck
out boldly for the shore. John was ahead of him, but he was soon
overhauled by the powerful negro and side by side the two swimmers
plowed through the sea. Behind them the waters were still churned by the
struggles of the great shark, but they were rapidly becoming weaker.

"Sam killed the shark," exclaimed Fred, almost overcome by the
suddenness and the unexpectedness of the event.

"It looks so," agreed Grant. "I didn't think it was possible."

"Nor I. Imagine the nerve he had, and that old knife certainly did do
the work after all."

"Well, John owes his life to Sam all right. He surely would have been
killed if he had been left out there alone."

"Not a doubt of it. I don't see how Sam managed it."

"We'll find out in a minute. John must be about exhausted too; Sam is
helping him in."

"Want any help, you two?" called Fred to the two swimmers who were
rapidly approaching the shore.

"No, thanks," said John in reply. "Sam will get us in."

Grant and Fred leaned far out over the water and extended their hands to
the two swimmers who were only a few feet distant now. A moment later
and they had drawn John up on the shore, where he lay panting, his
strength practically all used up. When they turned to assist Sam,
however, they found their negro friend clambering up without the least
bit of trouble.

"What's the matter with your shoulder, Sam?" exclaimed Grant in alarm.

The skin seemed to be all torn away and the blood was flowing freely
from Sam's right shoulder. Just what had happened, it was impossible to
say.

CHAPTER XX

TALKING IT OVER

"Dat," said Sam, referring to Grant's question concerning his shoulder,
"am wheah Ah come in too clost contack wif dat sha'k."

"Did he bite you?" exclaimed Fred.

"No, indeed. He jes' nachully done rub up again' me, dat's all."

"But just rubbing against you wouldn't tear you up like that," protested
Fred.

"Am dat so? Ah don't reckon yo' all evah seen a sha'k at front han' ef
yo' say dat. Have yo' evah felt a sha'k's skin?"

"No, I haven't. Is it rough?"

"Have you evah felt san' paper?"

"Lots of times. Is it as rough as that?"

"Lawdy," exclaimed Sam. "In compahson wif a sha'k's skin Ah tell yo' dat
san' paper am lak velvet."

"I should say it was rough, then," laughed Fred. "Doesn't that hurt?"

"It must," Gran